1blk
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1blk.gif|left|200px]] | [[Image:1blk.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1blk", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | + | --> | |
| - | + | {{STRUCTURE_1blk| PDB=1blk | SCENE= }} | |
| - | + | ||
| - | | | + | |
| - | }} | + | |
'''NMR ENSEMBLE OF BLK SH2 DOMAIN USING CHEMICAL SHIFT REFINEMENT, 20 STRUCTURES''' | '''NMR ENSEMBLE OF BLK SH2 DOMAIN USING CHEMICAL SHIFT REFINEMENT, 20 STRUCTURES''' | ||
| Line 31: | Line 28: | ||
[[Category: Mueller, L.]] | [[Category: Mueller, L.]] | ||
[[Category: Pryor, K.]] | [[Category: Pryor, K.]] | ||
| - | [[Category: | + | [[Category: Phosphorylation]] |
| - | [[Category: | + | [[Category: Phosphotransferase]] |
| - | [[Category: | + | [[Category: Signal transduction]] |
| - | [[Category: | + | [[Category: Transferase]] |
| - | [[Category: | + | [[Category: Tyrosine kinase]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 11:40:17 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 08:40, 2 May 2008
NMR ENSEMBLE OF BLK SH2 DOMAIN USING CHEMICAL SHIFT REFINEMENT, 20 STRUCTURES
Overview
Signal transduction in B cells is mediated, in part, by the interaction of the cytoplasmic components of the antigen receptor complex and various members of the src family tyrosine kinases. Key to this process appears to be the interaction of the tyrosine kinase SH2 domains with the tyrosine-phosphorylated cytoplasmic domain of Ig-alpha, a disulfide-bonded heterodimeric (with Ig-beta or Ig-gamma) transmembrane protein that noncovalently associates with the antigen receptor immunoglobin chains. In addition to binding to the phosphorylated cytoplasmic domains of Ig-alpha and Ig-beta, blk and fyn(T), two members of the src family kinases, have been shown to bind overlapping but distinct sets of phosphoproteins [Malek & Desiderio (1993) J. Biol. Chem. 268. 22557-22565]. A comparison of their three-dimensional structures may elucidate the apparently subtle differences required for phosphoprotein discrimination. To begin characterizing the blk/fyn/phosphosphoprotein interactions, we have determined the three-dimensional solution structure of the SH2 domain of blk kinase by nuclear magnetic resonance (NMR) spectroscopy. 1H, 13C, and 15N resonances of the SH2 domain of blk kinase were assigned by analysis of multidimensional, double- and triple-resonance NMR experiments. Twenty structures of the blk SH2 domain were refined with the program X-PLOR using a total of 2080 experimentally derived conformational restraints. The structures converged to a root-mean-squared (rms) distance deviation of 0.51 and 0.95 A for the backbone atoms and for the non-hydrogen atoms, respectively. The blk SH2 domain adopts the prototypical SH2 fold. Structurally, blk SH2 is most similar to the crystal structure of the v-src SH2 domain [Waksman et al. (1993) Nature 358.646-653] and superimposes on the crystal structure with an rmsd of 1.52 A for the backbone atoms. The largest deviations occur in the four loops interconnecting beta-strands A-E, which are the least well-defined regions in the NMR structure. Exclusion of these loops lowers this rmsd to 0.82 A. The conformation of the BC loop in the blk SH2 domain is similar to the open conformation in the apo lck SH2 domain, suggesting that, like the lck SH2 domain, the blk SH2 domain may have a gated phosphopeptide binding site. Finally, it is proposed that the amino acid substitution of Lys 88 (blk) for Glu [fyn(T)] is important for the observed differences in specificity between blk and fyn(T) SH2 domains.
About this Structure
1BLK is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
The three-dimensional solution structure of the SH2 domain from p55blk kinase., Metzler WJ, Leiting B, Pryor K, Mueller L, Farmer BT 2nd, Biochemistry. 1996 May 21;35(20):6201-11. PMID:8639560 Page seeded by OCA on Fri May 2 11:40:17 2008
